How to rotate a line using Matlab?

Suppose I have an image I and a line h1. Using Matlab, I can draw the line (or segment) like this (in red) :

    h1 = plot( [l1 l1],[20 100], 'r');

Now I want to rotate the image I with an angle of 45°. So I used imrotate like this:

    IR = imrotate(I,45);

Now, I want to rotate the line, how to do that using Matlab ?

PS: I found the function rotate. I am trying this, but it is not working !

    rotate(h1,[1 1],45);

Answer 1

[Image Analyst]

imrotate() rotates an entire image, not a line you created with line() or plot(). You need to take your points and multiply by the rotation matrix - you know, the sin and cos thing you learned in your linear algebra class in college. Then call line() or plot() again with the rotated coordinates.

[Makrim]

it worked for the two points of the line ... thank you

Answer 2

[Habtamu Tesfaw]

here is a simple package that can do the job '

https://www.mathworks.com/matlabcentral/fileexchange/88748-lrotate?s_tid=srchtitle